Jotaro has been raised by Mariko, Usagi's childhood sweetheart, and Kenichi, Usagi's rival. The boy is actually the offspring of Usagi and Mariko, from a coupling that occurred just before Usagi left to begin service with the the Mifune daimyate.

The boy has inherited many traits from Usagi, but has been brought up by Kenichi. As a small child, Jotaro was kidnapped by the Mogura Ninja, and again later by Jei who had been told by his inner voices to take the child. Each time the boy showed his own resourcefulness in freeing himself and making good his escape. The boy has no knowledge that Kenichi is not his real father.

Jotaro is now almost at the age to receive his Samurai topknot and will be advised by his father to go to the Dogora fencing school. Usagi has advised the boy to seek out Katsuichi. This may be a source of friction in the future, as the boy idolises Usagi.

During his incarceration by Jei, the boy befriended a tokage, whom he named Spot. Jotaro and Spot still reside in the village and will presumably do so until it is his turn to learn the ways of Bushido.